This invention relates generally to a television entertainment, education and training system. It relates more particularly to a system of that type which permits a standard television system to transmit digital, binary-coded data to the viewers along with the usual television picture. Alternatively, this program material can be contained on prerecorded tape and either broad or cable-cast, or directly played back by the viewer using a video playback machine.
Considerable thought and attention is being given to the use of television systems as an educational and training tool. This is because on the one hand, a single television broadcast can reach a very large number of people. Consequently, the "per pupil" cost of a particular television course is relatively low. Also, this arrangement permits many viewers to have the advantage of receiving instruction from the very best teachers. On the other hand, use of prerecorded video tape can bring personalized one-on-one teaching to a student.
To optimize the benefits to the viewers from the various courses, contests, training exercises, etc. offered by the television or video tape program originator, it is desirable that the individual viewer be able to interact with the program. To this end, it has been proposed that the program or transmitting facility send certain data to the viewers pertaining to the program without interfering with the program picture. One way of accomplishing this is to send the data as coded brightness modulation in small dedicated areas of the television picture frame as disclosed in U.S. Pat. No. 3,737,566 assigned to the assignee of the present application. The present invention pertains to a system of that general type.
As disclosed in the aforesaid patent, in a television course including a multiple choice quiz, for example, the correct quiz answers can be "tagged" by impressing unique brightness modulations in squares associated with the correct answers. However, the tagging of correct answers in that fashion involves the transmission of only a small amount of data. In many instances, it is desirable for the program originator to be able to send much more data to properly train or assist the individual program viewer, through his TV set or monitor and, possibly, other associated devices. To be practical, this must be accomplished without altering the standard television signal and without unduly obstructing the TV picture. If properly done, the brightness, binary-coded, high speed digital modulation must not only be unobtrusive to the casual viewer but should induce him to avail himself of the full benefit of the program he is watching by interactive participation using the appropriate equipment.